Dihalo substituted phosphoranylideneamino benzoouinones and method for their production



United States Patent DIHALO SUBSTITUTED PHOSPHORANYLIDENE- AMINO BENZOQUINONES AND METHOD FOR THEIR PRODUCTION William Lindsay Mosby, North Plainfield, Helen Currier Gillham, Princeton, and Allan Ellis Sherr, Martinsville, N.J., assignors to American 'Cyanamid Company, Stamford, Conn., a corporation of Maine No Drawing. Original application Feb. 17, 1964, Ser. No. 345,075, now Patent No. 3,322,860, dated May 30, 1967. Divided and this application Dec. 19, 1966, Ser. No. 602,465

Int. Cl. C07f 9/54; C09k 3/28 US. Cl. 260--396 8 Claims ABSTRACT OF THE DISCLOSURE A process for the production of dihalo substituted phosphoranylideneamino benzoquinones and the compounds per se are disclosed.

This application is a division of our copending application, Serial No. 345,075, filed February 17, 1964 and now US. Patent No. 3,322,860.

The search for compounds, mixtures of compounds or compositions of matter as flame retardants for thermoplastic polymers has been intensively conducted industrially. The use of materials containing phosphorus and/ or nitrogen atoms as flame-retardant additives for some polymers has been recognized, as has been the use of various halogenated materials such as the halogenated styrene copolymers and various additive mixtures such as chlorinated paraifin wax with triphenyl stibine, chlorinated paraflins with aliphatic antimony compounds, and antimony-oxide-chlorinated hydrocarbon mixtures. A drawback, however, in regard to the known prior art materials which have been used as flame retardants, has been the fact that generally a large amount, i.e. upwards of 35%, of the additive must be incorporated into the polymer in order to make it sufliciently flame retardant. Additionally, the known flame retardant additives have a tendency to crystallize or oil out of the resin a relatively short time after incorporation.

We have found a new group of compounds which may be added to thermoplastic resins, in relatively small amounts, to produce excellent flame-retardant compositions. A further feature resides in the fact that these new additives do not crystallize or oil out after incorporation intd the resin.

The production of thermoplastic resin compositions which are flame-retardant, i.e. have high resistance to burning, is of considerable importance commercially. For example, such articles as castings, moldings, foamed or laminated structures and the like are required, or at least desired, to be resistant to fire and flame and to possess the ability to endure heat without deterioration. Typical illustrations of applications of materials of this type include moldings for live electrical contacts which should not be ignited or deteriorated by heat and sparks. Additionally, structural members such as pipes, wall coverings, wall paneling, glazing, etc. and articles such as ash trays, waste baskets, fibers and the like are further 3,439,005 Patented Apr. 15, 1969 "ice examples of products wherein flame retardance is desirable.

It is therefore an object of the present invention to provide a novel class of compounds and a method for the production thereof.

It is a further object of the present invention to provide a method for the production of a novel class of dihalo substituted phosphoranylideneamino benzoquinones and the compounds per se.

It is a further object of the present invention to provide flame-retardant compositions comprising thermoplastic polymers containing a flame-retarding amount of a dihalo substituted phosphoranylideneamino benzoquinone.

These and other objects will become more apparent to those skilled in the art upon reading the more detailed description set forth hereinbe'low.

The novel method and compounds The novel dihalo substituted phosphoranylideneamino benzoquinones of the instant invention are represented by the formula wherein X is a chlorine, bnomine or iodine radical and R is a phenyl, naphthyl, substituted phenyl or substituted naphthyl radical said substituents being halogen, lower alkyl or lower alkoxy radicals.

These compounds are solid in nature and have relatively high melting points, e.g., as high as 360 C. They are soluble in such organic solvents as chloroform, pyridine, quinoline, dimethylformamide, dimethylsulfoxide, dimethyacetamide and the like.

The compounds of Formula I may be produced, :according to our novel procedure, by reacting a 2,S-dihalo-3,6- diaminobenzoquinone with a trisubstituted, i.e. (R) phosphinium dihalide. The reaction proceeds according to the equation:

wherein R and X are as set forth hereinabove in regard to Formula I, and X is a halogen radical.

The reaction is preferably carried out at room temperature and atmospheric pressure, although higher or lower temperatures and pressures may be used if circumstances so dictate, and in the presence of an organic base, such as triethyl amine as a hydrogen halide acceptor 3 and a solvent, such as toluene or chlorobenzene. Other acceptors which may be used include trimethylamine, pyridine and the like while ethylene glycol dimethyl ether, benzene and the like are examples of other solvents. The amounts of each of these compounds used are not critical, however enough of each should be employed to carry out their function as acceptor and solvent, respectively.

The reaction is generally allowed to continue for from about /2 to 4 hours although this range is not critical and shorter or longer times of contact may be used if necessary.

The molar ratio of the phosphinium halide to the dihalobenzoquinone used is about 2:1, however, it is preferable to utilize a slight excess of the phosphinium halide over said ratio to insure complete reaction of the available -NH groups of the benzoquinone.

The products may be recovered by filtration, centrifugation etc. and may then be further purified by recrystallization and the like.

The phosphinium dihalide reactant may conveniently be prepared by reacting a trisubstituted, i.e. (R) phosphine with a halogen, e.g. bromine, in a solvent such as chlorobenzene, under known conditions, while the benzoquinones are also well known and can be prepared as set forth, for example, in an article by von Knapp et al., Annalen der Chemie, volume 210, page 184, 1881.

Compounds which are represented by Formula I and which can be used to produce our novel flame-retardant compositions include:

2,5-dichloro-3,6-bis (triphenylphosphoranylidene amino p-benzo quinone,

2,5-dibromo-3,6-bis triphenylphosphoranylideneamino) p-benzo quinone,

2, S-diio do-3 ,6-bis (triphenylphosphoranylideneamino p-b enzoquinone,

2,5-dichloro-3,6-bis [tris( 1-naphthyl)phosphoranylidene amino] -p-benzoquinone,

2,5-dibromo-3,6-bis [tris( l-naphthyl) phosphoranylideneamino] -p-benzoquinone,

2,5-diiodo-3,6-bis [tris( l-naphthyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3,6-bis [tris(p-chlorophenyl phosphoranylideneamino] -p-b enzo quinone,

2,5-dibromo-3 6-bis [tris (p-chlorophenyl phosphoranylideneamino] -l -b enzoquinone,

2,5-diiodo-3,-6-bis [tris (p-chlorophenyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3 ,6-bis [tris (o-bromophenyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dibromo-3,6-bis [tris (2,4-dichlorophenyl) phosphoranylideneamino] -p-b enzoquinone,

2,5-diiodo-3 ,6-bis [tris (2,4-dichlorophenyl) phosphoranylideneamino] -p-b enzoquinone,

2,5-dichloro-3,6-bis [tris(m-iodophenyl) phosphoranylideneamino] -p-b enzo quinone,

2,5 -dibromo-3,6-bis [tris (p-fluorophenyl) phosphoranylideneamino] -p-benzquinone,

2,5-diiodo-3,6-bis [tris (p-fluorophenyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3 ,6-bis [tris (p-methylphenyl) pho sphoranylidene amino] -p-b enzo quinone,

2,5-dibromo-3,6-bis [tris(2,4-dimethylphenyl) phosphoranylideneamino] -p-b enzo quinone,

2,5-diiodo-3 ,6-bis [tris 2,4-dimethylphenyl phosphoranylideneamino] -p -b enzo quinone,

2,5-dichloro-3 ,6-bis [tris m-t-butylpheuyl )phosphoranyl ideneamino] -p-benzoquinone,

2,5-dibromo-3,6-bis [tris (m-t-butylphenyl) phosphoranylidenamino] -p-benzoquinone,

2,5-diiodo-3,6-bis [tris (m-t-butylphenyl) phosphoranylideneamino] -p-b enzo quinone,

2,5 -dichloro-3,6-b is [tris (o-n-butylphenyl phosphoranylideneamino] -p-b enzoquinone,

2,5-dichloro-3,6-bis [tris (p-methoxyphenyl) phosphoranylideneamino] -p-b enzo quinone,

2,5-dibromo-3,6-bis [tris (m-butoxyphenyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dibromo-3,6-bis [tris( l-methyl-Z-naphthyl phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3,6-bis [tris 3-n-butyl-1-naphthyl) phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3 ,6-bis [tris (4-chloro-1-naphthyl) phosphoranylidene-amino] -p-benzoquinone,

2,5-dibromo-3,6-bis [tris S-bromo-Z-naphthyl phosphoranylideneamino] -p-benzoquinone,

2,5-dibromo-3 ,6-bis[tris(Z-iodo-1-naphthyl)phosphoranylideneamino] -p-benzoquinone,

2,5-dichloro-3 ,6-bis [tris 3-methoxy-2-naphthyl) phosphoranylideneamino] -p-benzo quinone,

2,5-diiodo-3,6-bis [tris( 1-nbutoxy-2-naphthyl)phosphoranylidene-amino] -p-b enzoquinone,

and the like.

The novel flame-retardant compositions The thermoplastic polymers into which the novel polymers of our invention may be incorporated to produce the novel flame retardant compositions of the present invention, are generally the vinyl type polymers wherein the monomeric material is polymerized, by any known method, via the vinyl unsaturation therein. Examples of the vinyl type polymers which may be used to form our novel compositions are the acrylates and methacrylates, the vinyl halides, the vinylidene halides, the vinyl acetates, polyvinyl butyral, butadiene copolymers, acrylonitrilebutadiene-styrene polymers, the acrylonitriles, etc. Additionally, and preferably, one may incorporate the flame retardant agents mentioned above into such polymers as the a-olefin polymers, such as the homopolymers and copolymers, etc. containing, as the major constituent, ethylene, propylene, and the like and the acrylates and methacrylate polymers produced from monomers having the formula CH=C=G/ where R is a hydrogen or methyl radical and R is a hydrogen or an alkyl radical having from 1 to 6 carbon atoms, inclusive. Examples of monomers represented by Formula II include acrylic acid, methacrylic acid and their esters such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate, n-amyl acrylate, t-amyl acrylate, hexyl acrylate, and the corresponding alkyl methacrylates.

Additional examples of monomers which may be used to form the thermoplastic vinyl polymers encompassed by the present invention, polymerized either singularly or in combination with each other or with the other compounds set forth hereinabove, are such monomers as the unsaturated alcohol esters, more particularly, the allyl, methallyl, vinyl, methvinyl, butenyl, etc., unsatunated esters of aliphatic and aromatic monobasic acids, such, for instance, as acetic, propionic, butyric, crotonic, succinic, glutaric, adipic, maleic, fumaric, itaconic, benzoic, phthalic, terephthalic, benzoylphthalic, etc., acids; the saturated monohydric alcohol esters, e.g., the methyl, propyl, ethyl, isopropyl, butyl, sec.-butyl, amyl, etc., esters of ethylenically unsaturated aliphatic monobasic acids, illustrative examples of which appear above; vinyl cyclic compounds (including monovinyl aromatic hydrocarbons), e.g., styrene, 0-, m-, and p-chlorostyrenes, -bromostyrenes, fiuorostyrenes, -methylst-yrenes, -ethylstyrenes, -cyanostyrenes, the various poly-substituted styrenes such, for example, as the various di-, tri-, and tetra-chlorostyrenes, -bromostyrenes, fiuorostyrenes, -methylstyrenes, -ethylstyrenes, -cyanostyrenes, etc., vinyl pyridine, divinyl benzene, diallyl benzene the various a-llyl cyanostyrenes, the various alpha-substituted styrenes and alpha-substituted ring-substituted styrenes,

e.g., alpha-methyl styrene, alpha-methyl-para-methyl styrene, etc.; unsaturated ethers, e.g., ethyl vinyl ether, diallyl ether, etc.; unsaturated amides, for instance, N- allyl caprolactam, acrylamide and N-substituted acrylamides, e.g., N-methylol acrylamide, N-allyl acrylamide,

retardant additive may be combined with the resin by milling the resin and the flame retardant benzoquinone on, for example, a two-roll mill, in a Banbury mixer, etc., or the benzoquinone may be added by molding it and resin simultaneously, extruding it and the resin or 5 N-methyl acrylamide, N-phenyl acrylamide, etc.; unsatuby merely blending the resin in powder form with the rated ketones, e.g., methyl vinyl ketone, methyl allyl benzoquinone and thereafter forming the final desired ketone, etc.; methylene malonic esters, e.g., methylene article. Additionally, the novel flame-retardant commethyl malon'ate, etc. and ethylene. pounds may also be added during the resin manufacture,

Other examples of monomers that can be used as i.e. during the monomer polymerization procedure, propolymers to form the resin portion of our novel flamevided the catalyst etc., and other ingredients of the retardant compositions are the vinyl halides, more parpolymerization system are inert thereto. ticularly, vinyl fluoride, vinyl chloride, vinyl bromide, It is within the scope of the present invention to inand vinyl iodide, and the various vinylidene compounds, corporate such ingredients as plasticizers, dyes, pigments, including the vinylidene halides, e.g., vinylidene chloride, fillers, stabilizers, antioxidants, antistatic agents and the vinylidene bromide, vinylidene fluoride, and vinylidene like to our novel compositions without detracting from iodide, other comonomers being added, if needed, in the advantageous properties thereof. order to improve the compatibility and copolymerization The following examples are set forth for purposes of characteristics of the mixed monomers. illustration only and are not to be construed as limitations More specific examples of allyl compounds that can 2 on the present invention except as set forth in the apbe polymerized to useful polymers, useful in the propended claims. All parts and percentages are by Weight duction of our novel flame-retardant compositions, are unless otherwise specified. allyl alchohol, methallyl alcohol, diallyl carbonate, allyl lactate, allyl methacrylate, allyl alphahydroxyisobutyrate, Example 1 allyl triehlorosilane, diallyl phthalate, dially metht-ylgluconate, tartronate, tartrate, mesaconate, parts of triphenyl phosphine are dissolved in h lf ester dlallyl chlofophthala'te, parts of dry chlorobenzene and to the resultant mixture diallyl dichlorosilane, the diallyl ester of endomethylene i dd d 3 1 6 of 352 parts of b i i 10 pal-ts y p yq tflallyl Y f" of dry chlorobenzene. The addition is carried out with allyl cyanufate, tflallyl ISPCYaIIUIate, l y (filtrate, stirring, accompanied by cooling in an ice bath to prol lf Phosphate, f y sllane, tetrallyl 511168116, heXallyl duce the resultant trip'henylphosphiniurn dibromide. disiloxane, allyl digylcol carbonate, etc. Other examples T thi ixt re, after Warming to room temperature, of allyl compounds that y be p y elven, for are then added 2.07 parts of 2,5-dichloro-3,6-diaminop In Patent 2,510,503, Issued June 6, benzoquinone, 6 parts of triethyl amine and 25 parts of 1950- chlorobenzene. The mixture is refluxed with stirring until These above mentioned monomers may be polymerized, the reaction is complete (approximately one hour) and copolymerized, etc., in any known manner such as by the solid material is then removed by filtration and freeradical generating catalysts, irradiation, a ion a d Washed with chlorobenzene. The solid material is Washed cation type catalysts 'and the like, said method of polymfurther with water to remove Water-soluble salts and erization forming no part of the present invention. finally with methanol. After drying, th P The novel flame-retardant compounds may be incorpodlchloro 3,6-b1s(triphenylphosphoranylideneamino) prated into the thermoplastic resins in flame-retarding benzoquinonqis obtalned in solid form (6.8 parts) with amounts, i.e. generally amounts ranging from about 10%, a melting point greater than 360 C. by weight, to about 35%, by weight, preferably 15% to Following the procedure of Example 1, various phos- 25%, by weight, based on the weight of the resin have phinium dihalides were reacted with diaminobenzobeen found sufficlent. quinones to produce the corresponding phosphoranyli- These benzoquinones may be incorporated into the deneamino benzoquinones according to the present inresin by any known method. That is to say, the flamevention. The results are set forth hereinbelow in Table I.

TABLE I Ex. Phosphim'um Dihalide Diaminobenzoquinone Temp, 0. Product 2 Tris(l-naphthyl)phosphinium dibro- 2,5dichl0ro-3,6-diamino- 23 2,5dichl0r0-3,6-bis[tris(1-naphthyl)phosphoranylidenemide. benzoquinone. amino1-p-benzoquinone. 3 Tris(p-chlorophenyl)phosphinium 2,5-dibromo3,6-diamino- 23 2,5-dibromo-3,fi-bis[tris(p-chlorophenyl)phosphoranyldichloride. benzoquinonet ideneamino1-p-benzoquinone. 4 Tris(abromophenybphosphininm 2,5-diiodo-3,6-diaminobenzo- 2,5diiodo-3,6-bis[tris(o-bromophenyl)phosphoranylbromide. quinone. ideneamino]p-benzoquinone. 5 Tris(2,4-difiuorophenyD-phosphinium 2,5-d.ichl0ro3,6-diamino- 50 2,5-dich10ro-3,6-bis[tris(2,4-difluorophenyl) phosphoranyldibromide. benzoquinone. ideneamino1-p-benzoquinone. 6 Tris(p-methylpheuyhphosphininm .d0 2,5-dicl110r0 3,6-bis[tris(p-methylphenyl)phosphoranyldibromide. ideneamino1-p-benzoquinone. 7 Tris(p-n-butylphenyl)phosphinium 2,5-dibromo-3,6-diamino- 2,5'dibr0mo-3,6-bis[tris(p-n-butylphenyl)phosphoranyldiiodide. benzoquinone. ideneamino]-p-benz0quinone. 8 Tris(m-methoxyphenyl)phosphinium 2,5-dichloro-3,6-diamin0- 2,5-dichloro-3,7-bis[tris(m-methoxyphenyl)phosphoranyldibromide. beuzoquinone. ideueamino]-pbenzoquinone. 9 Tris(p-butoxyphenyDphosphinium 2,5-diiodo-3,6-diamino- 75 2,5-dii0d0-3,G-bis[tris(p-butoxyphenyl)phosphoranyldibromide. benzoquiuone. ideneamino1-p-benzoquinone. 10 Tris(2-methyl-1-naphthy1) phos- 2,5-diehloro-3,6-diamino- 23 2,5-dichlor0-3,6-bis[tris(2-methyl-l-naphthyl) phosphorphinium dibromide. benzoquinone. anylideneamino1-p-benzoquinone. 11 Tris(3-butyl-2naphthyl)phos- 2,5-dibromo-3,6-diamino- 23 2,5-dibromo-3 6-bis[tris(3-butyl-2-naphthyl)phosphor-amylphinium dibromide. benzoquinone. ideneamino -p-benzoquinone. 12 Tris(1-methoxy-2-naphthyl) phos- 2,5-dichloro-3,6-diamino- 23 2,5-dichloro-3,t bis[tris(l-methoxy-Z-naphthyl) phosphorphinium dibrorm'de. beuzoquinone. anylideneamino1-p-benzoquinone.

-do 2,5diChl010-3,fi'bis[tris(S-butoxy-l-naphthyl) phosphor- 13 Tris(5-butoxy-l-naphthyl) phosphinium dibromide.

14.- Tris (3-chloro-2-naphthyl) phos- 2,5-dibromo-3,6-diaminophinium dibromide. benzoquinone.

15 Tris (ti-bromo-l-naphthyl) phos- 2,5-dichloro-3,6-diaminophinium dibromide. benzoqninone.

16 Tris (4-i0 do-Z-naphthyl) phosphinium .do

dibromide.

anylideneamino]-p-beuzoquinone. 2,5-dibro1'no-3,6-bis[tris(3-cl1l0r0-2-naphthyl)phosphoranylideneamino]-p-beuz0quinone. 2,5-dichloro-3,6bis[tris(fi-bromo-l-naphthyl) phosphoranylideneamino1-p-benzoquinone. 2,5-dichloro-3,6-bis[tris(4-iodo-2-naphthyl)phosphoranylideaneamino1-p-benzoquinone.

Any appropriate flame retardance 'test may be used to determine the flame retardant properties of any specific composition of the present invention. One test which is reasonably eflicient is that designated as a modified version of ASTM test D-635-56T. The specifications for this test are: a specimen, in length, 0.5" in Width and 0.045" in thickness, is marked at the -1" and 4" lengths and is then supported with its longitudinal axis horizontal and its transverse axis inclined at 45 to the horizontal. A Bunsen burner with a 1" blue flame is placed under the free end of the strip and is adjusted so that the flame tip is just in contact with the strip. At the end of 30 seconds, the flame is removed and the specimen is allowed to burn. If the specimen does not continue to burn after the tfirst ignition it is immediately recontacted with the burner for another 30 second period. If after the two burnings, the strip is not burned to the 4" mark, the specimen is designated as self-extinguishing or flameretardan Example 17 Eighty (80 parts of polyethylene and 20 parts of 2,5- dichloro 3, 6 bis(triphenylphosphoranylideneamino)- p-benzoquinone are rolled together on a two-roll mill at about 170 C. The resulting milled composition is molded into strips 5" in length, 0.5" in width and 0.045" in thickness and said strips are then subjected to an art recognized flame retardance test. The strips pass the test and are therefore designated as flame retardant.

Following the procedure of Example 17, the following examples were carried out utilizing various flame retardants of the instant invention and various thermoplastic resin polymers. The results of these examples are set forth in Table II, below. In each instance, the resultant composition passed the flame-retardance test and was designated as flame and fire retardant. In the table, PE =polyethylene, PAN=polyacrylonitrile, PP=polypropylene, PMMA=poly(methyl methacrylate), PMA=poly- (methacrylic acid), PA=poly(acrylic acid), AN=acrylonitrile, ST=styrene and BD=butadiene.

TABLE II Flame-Retardant Ex. Resin Compound Per- Produced In cent Example Number- 18- PMMA terpolymer 1 15 19 MMA/ST/AN 71/19/10 4 25 20- PP 2 25 21.-.- PE 3 20 22---. PMMA 2 15 23.--. Mixture of BD/AN (IO/75%) and 1 25 AN/ST (25/90%). 24-..- A 6 25 10 20 26..--.. 27---- 7 13 20 11 25 5 10 8 9 20 6 15 12 v 30 PP 14 25 86-..- Same as 2 16 25 1 U.S. Patent 2,349,202.

8 We claim: 1. A compound having the formula wherein X is selected from the group consisting of chlorine, bromine and iodine radicals and R is selected from the group consisting of phenyl, naphthyl, substituted phenyl and substituted naphthyl radicals, said substituents being selected from the group consisting of halogen, lower alkyl and lower alkoxy radicals.

2. A compound according to claim 1 wherein R is a phenyl radical.

3. A compound according to claim 1 wherein X is chlorine.

4. A compound according to claim 1 wherein R is a phenyl radical and X is chlorine.

5. A method for the'production of a compound according to claim 1 which comprises reacting a dihalobenzoquinone having the formula wherein X is as defined above, with a phosphinium halide having the formula wherein R is defined as above and X is a halogen radical, in the presence of a hydrogen halide acceptor and a solvent and at a molar ratio of phosphinium halide to dihalobenzoquinone of at least about 2:1, respectively.

6. A method according to claim 5 wherein R is a phenyl radical.

7. A method according to claim 5 wherein X is chlorine.

8. A method according to claim 5 wherein R is a phenyl radical and X is chlorine.

References Cited UNITED STATES PATENTS 3,223,716 12/1965 Mosby et al. 260-396 LORRAINE A. WEINBERGER, Primary Examiner.

L. A. THAXT ON, Assistant Examiner. 

